JP2005215463A - Camera device and dew condensation preventing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently prevent dew condensation of a window member of a camera device. <P>SOLUTION: This camera device is characterized in that: a dome 22 is the window member for photography; a lens whose direction is changeable is provided inside the dome 22; a fan of a fan heater unit 42 generate a wind for dew condensation prevention; and the wind is discharged from a nozzle 44 held by the lens 16 to change in direction together with the lens 16. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a camera device having a structure for preventing condensation.

  In a surveillance camera installed outdoors, when the outside air temperature drops rapidly, condensation forms on the inner surface of the camera case, and this condensation causes deterioration of the surveillance image. Therefore, in order to prevent image deterioration, a dew condensation prevention device may be provided in the camera.

2. Description of the Related Art Conventionally, as a dew condensation prevention device for a camera, a device in which a fan for air blowing is provided in a camera case and air is blown from a fan to a window glass is known (for example, see Patent Document 1).
JP 2003-198899 A (second page, FIG. 1)

  However, in the case of a camera in which the window member is relatively large and the direction of the lens can be changed, such as a dome-type surveillance camera, it is not easy to prevent the entire condensation of the window member. There is a problem that it is not easy to prevent condensation even when facing. Further, in the dome-type surveillance camera, since the gap between the lens and the window member is small, there is a tendency that condensation is likely to occur in front of the lens, and prevention of such condensation is desired.

  The present invention has been made to solve the conventional problems, and an object of the present invention is to provide a camera device that can effectively prevent dew condensation.

  The camera device according to the present invention includes a window member for photographing, a lens that is disposed inside the window member, the direction of which can be changed, a fan that generates wind for preventing dew condensation, and the lens beside the lens. And a nozzle that discharges the wind generated by the fan. The nozzle is held beside the lens by nozzle holding means.

  With this configuration, since the nozzle is held beside the lens, the direction of the nozzle is changed with the change of the direction of the lens, and condensation of the window member can be efficiently prevented so that a good image can be obtained.

  In addition, the camera device of the present invention includes a heater for supplying warm air to the nozzle. With this configuration, warm air can be blown onto the window member, and condensation can be more reliably prevented.

  The camera device of the present invention has a slip collar rotatably attached to the lens barrel of the lens, and the nozzle is attached to the slip collar.

  With this configuration, the slip collar rotates as the lens direction changes, so that the nozzle can be held beside the lens facing an arbitrary direction without imposing an excessive load on the nozzle. For example, even when the gap around the lens is small, damage to the nozzle can be prevented.

  In addition, the camera device of the present invention includes a plurality of nozzles around the lens. In this configuration, a plurality of separate nozzles may be provided from the root, or a single nozzle may be branched into a plurality of nozzles to be arranged on the side of the lens. With this configuration, condensation in front of the lens can be prevented more reliably.

  The camera device of the present invention includes a temperature sensor and a humidity sensor, and fan heater control means for controlling the fan and the heater according to the temperature and humidity detected by the temperature sensor and the humidity sensor. With this configuration, power consumption of the fan and heater can be suppressed.

  In addition, the dew condensation prevention apparatus of the present invention is a lens that can change the direction in which a fan that generates wind for preventing dew condensation, a nozzle that discharges the wind generated by the fan, and the window member for photographing is arranged. And a nozzle holding means for holding the nozzle. Also with this configuration, since the nozzle is held beside the lens, condensation of the window member can be efficiently prevented.

  The present invention can provide a camera device having an effect that the condensation of the window member can be efficiently prevented by holding the nozzle on the side of the lens.

  Hereinafter, a camera device according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view of a camera device according to a first embodiment of the present invention, FIG. 2 is a perspective view of the camera device installed on a ceiling, and FIGS. 3 and 4 are exploded views. In the present embodiment, the camera device 10 is a dome type surveillance camera.

  1 to 4, the camera device 10 includes a base 12 and a cover 14 that constitute a housing. The base 12 is circular as a whole, and has a structure for mounting to an installation location such as a ceiling. The base 12 supports the lens 16 so as to be rotatable in the pan direction and the tilt direction. The lens 16 is held by a lens barrel 18, and an image sensor is provided at the rear end of the lens barrel 18, and these constitute a camera.

  The cover 14 has a ring portion 20, and a dome 22 is attached to the ring portion 20 with screws. The ring portion 20 has an attachment structure to the base 14. The dome 22 is a window member and is made of a transparent plastic. As illustrated, the dome 22 has a shape that allows the lens 16 to be accommodated in the dome 22 when the cover 14 is attached to the base 12, whereby the lens 16 is disposed inside the window member.

  Referring to FIG. 3, as the pan / tilt structure of the lens 16, first, the lens 16 is rotatably attached to the base 12 by the pan portion 24. The pan portion 24 is provided with two support columns 26, and the lens 16 is rotatably supported between the two support columns 26, thereby realizing tilt rotation. In addition, an azimuth configuration 28 is provided to correct a change in the angle of the shooting range due to pan and tilt. In the present embodiment, the pan operation and the tilt operation are performed manually.

  Next, the dew condensation prevention apparatus 40 of this Embodiment is demonstrated. The dew condensation prevention device 40 includes a fan heater unit 42, a nozzle 44, and a slip collar 46.

  The fan heater unit 42 is attached to a position inside the circular wall of the base 12 so as not to interfere with the lens 16. The fan heater unit 42 includes a heater and a fan in a plastic case, and the fan sends out air heated by the heater, thereby generating hot air for preventing condensation.

  The nozzle 44 is composed of a hose attached to the side surface of the plastic case of the fan heater unit 42. The hose is a bellows type and can be bent flexibly. A flexible hose other than the bellows may be applied. The nozzle 44 guides the warm air generated by the fan heater unit 42 and discharges it from the discharge port 48 at the tip.

  The slip collar 46 is a member that holds the nozzle on the side of the lens. The slip collar 46 is a plastic ring, has an inner diameter slightly larger than the lens barrel 18 of the lens 16, and is attached to the distal end portion of the lens barrel 18 so as to be freely rotatable. For example, the tip of the lens barrel 18 is slightly enlarged to form a flange, and a claw hooked on the flange is provided on the slip collar 46, so that the slip collar 46 can be freely removed without dropping from the lens barrel 18. Can rotate.

  The slip collar 46 is provided with a retaining ring 50. A discharge port 48 at the tip of the nozzle 44 is attached to the holding ring 50. The holding ring 50 is provided so that the discharge port 48 faces the photographing direction (optical axis direction) beside the lens 16. With such a configuration, the nozzle 44 is held beside the lens 16.

  FIG. 5 is a functional block diagram showing a configuration for controlling the fan heater unit 42. In FIG. 5, the control device 60 includes a temperature sensor 62 and a control unit 64 to which the temperature detected by the temperature sensor 62 is input. The temperature sensor 62 is provided in the case of the fan heater unit 42 and detects the temperature in the dome. The control unit 64 controls the fan 66 and the heater 68 based on the temperature detected by the temperature sensor 62. In the present embodiment, the control unit 64 sends a control signal to the power supply switch to the fan 66 and the heater 68 to control on / off of the fan 66 and the heater 68. The control unit 64 is constituted by a microcomputer, for example. The control unit 64 may be configured with an electric circuit.

  FIG. 6 is a diagram illustrating control of the fan 66 and the heater 68. As shown in the figure, the heater 68 is turned off at 20 degrees when the temperature rises and is turned on at 10 degrees when the temperature falls. The fan 66 is turned off at 40 degrees when the temperature rises and is turned on at 30 degrees when the temperature is lowered. Thus, hysteresis is set for each of the fan 66 and the heater 68.

  Next, a method for assembling the camera device 10 according to the present embodiment will be described. In the state of FIG. 3, the lens 16 has already been assembled to the base 12 so that panning and tilting operations are possible. In this state, the lens 16 is directed, for example, in the dome zenith direction. The fan heater unit 42 is attached to a predetermined location inside the circular wall of the base 12. A nozzle 44 is attached to the fan heater unit 42 in advance. A slip collar 46 is attached to the tip of the lens 16. The slip collar 46 is fitted at the tip of the lens 16. The claw of the slip collar 46 is hooked on the lens 16, and the slip collar 46 is attached to the lens 16 so as to be rotatable without dropping off. The slip collar 46 may be attached to the lens 16 in advance before the lens 16 is attached to the base 12.

  Next, the lens 16 is oriented in a desired direction using a pan / tilt mechanism. Then, the discharge port 48 at the tip of the nozzle 44 is attached to the holding ring 50 of the slip collar 46. It is inserted into the holding ring 50 from the rear side so that the discharge port 48 faces forward. When the discharge port 48 is attached to the holding ring 50, the slip collar 46 is turned. As a result, the holding ring 50 is disposed at an appropriate location so that an excessive load is not applied to the nozzle 44, that is, the nozzle 44 is not bent excessively or pulled excessively.

  Further, the nozzle 44 may be attached to the slip collar 46 before changing the direction of the lens 16. In this case, when the direction of the lens 16 is changed, the slip collar 46 is rotated so that an excessive load is not applied to the nozzle 44, or the slip collar 46 is rotated by itself.

  After the dew condensation prevention device 40 is provided as described above, the cover 14 is screwed to the base 12 at three locations, and the assembly of the camera device 10 is completed.

  In the camera device 10 according to the present embodiment, the length of the hose of the nozzle 44 is set so that the slip collar 46 is turned to an appropriate position and the hose is appropriately bent regardless of the direction in which the lens 16 faces. The hose is set to fit in the space between the dome 22 and the lens 16 when it is extended or extended. With such a length setting, the nozzle 44 is assembled without receiving an excessive load as described above. Also in the example of FIG. 1, the nozzle 44 is appropriately bent and reaches the tip of the lens 16.

  Next, the operation of the camera device 10 according to the present embodiment will be described. First, it is assumed that the temperature is relatively high, 30 degrees or more, and neither the fan 66 nor the heater 68 is operating. At this time, the dew condensation prevention device 40 is not functioning. When the temperature decreases and the temperature detected by the temperature sensor 62 becomes 30 degrees or less, the control unit 64 sends a control signal to the fan 66 to turn on the fan 66. Thereby, a wind for preventing condensation is generated, and this wind is guided by the nozzle 44 and blown to the dome 22 from the side of the lens 16, thereby preventing condensation. The air blowing is performed in front of the lens 16, and therefore, condensation in a place necessary for photographing is efficiently prevented.

  When the temperature further decreases and the temperature detected by the temperature sensor 62 becomes 10 degrees or less, the control unit 64 sends a control signal to the heater 68 to turn on the heater 68. Thereby, warm air is generated, guided by the nozzle 44 and blown to the dome 22. The generation of hot air increases the ability to prevent condensation.

  Conversely, when the temperature rises, the operation is stopped in the order of the heater 68 and the fan 66. That is, the heater 68 stops when the temperature reaches 20 degrees, and the fan 66 also stops when the temperature reaches 40 degrees.

  The camera device 10 according to the first embodiment of the present invention has been described above. According to the first embodiment, since the nozzle 44 is held beside the lens 16, the direction of the nozzle 44 also changes with the change of the direction of the lens 16, and therefore, no matter which direction the lens 16 faces. Condensation in front of the lens 16 can be prevented, and condensation on the window member can be efficiently prevented.

  And according to this Embodiment, since the dew condensation ahead of the lens 16 can be prevented effectively as mentioned above, the fan 66 may have a low output, and this can suppress power consumption.

  Further, in the dome type camera as in the present embodiment, as shown in FIG. 1, the gap between the lens 16 and the dome 22 is narrow, and the air in the gap is difficult to flow. Therefore, although the front of the lens 16 is most important for photographing, condensation tends to occur in front of the lens 16. In the present embodiment, such condensation on the front side of the lens 16 can be effectively prevented, whereby a good image can be obtained.

  Moreover, according to this Embodiment, since the heater 68 for supplying a warm air to the nozzle 16 was provided, a warm air can be sprayed on a window member and condensation can be prevented more reliably. The capacity of the heater 68 can also be set low for the same reason as that of the fan 66, thereby reducing power consumption.

  Further, according to the present embodiment, the nozzle 44 is attached to the slip collar 46 that is rotatably attached to the lens barrel 18 of the lens 16, whereby the slip collar 46 is changed in accordance with the change in the direction of the lens 16. Therefore, the nozzle 44 can be held beside the lens 16 facing an arbitrary direction without imposing an excessive load on the nozzle 44. Even when the gap around the lens 16 is small, the nozzle 44 can be prevented from being damaged.

  Further, according to the present embodiment, the fan and the heater are controlled according to the temperature detected by the temperature sensor, thereby suppressing power consumption.

  FIG. 7 schematically shows a dew condensation prevention device in the camera device according to the second embodiment of the present invention. In the present embodiment, a plurality of nozzles are provided around the lens.

  In FIG. 7, two nozzles 80 and 82 are attached to the fan heater unit 42. The nozzles 80 and 82 are attached to both sides of the lens 16. That is, the slip collar 84 is provided with holding rings 86 and 88 at positions 180 degrees apart, and the tips of the nozzles 80 and 82 are attached to the holding rings 86 and 88, respectively, so that the nozzles 80 and 82 sandwich the lens 16 therebetween. Located on the opposite side.

  In the present embodiment, the wind (or warm air) generated by the fan heater unit 42 is guided through the two nozzles 80 and 82 and blown forward from both sides of the lens 16. By using a plurality of nozzles, the ability to prevent condensation can be increased.

  Within the scope of the present invention, in the configuration in which a plurality of nozzles are provided around the lens, the nozzles may not be fundamentally separate. That is, there is one nozzle at the attachment portion to the fan heater unit 42, and the nozzle branches in the middle. As a result, a plurality of nozzles are configured on the tip side, and the plurality of nozzles are arranged around the lens. May be. Further, the number of nozzles may be three or more.

  FIG. 8 shows a control device in the camera device according to the third embodiment of the present invention. As is apparent from comparison with the control block diagram of the first embodiment, a humidity sensor 92 is added to the control device 90 of FIG. 8, and the humidity detected by the humidity sensor 92 is input to the control unit 94. The humidity sensor 92 is provided at a location outside the imaging range inside the dome 22. The place outside the imaging range is, for example, a place around the dome 22 and hidden by the base 12. Further, the humidity sensor 92 may be provided in a lens support structure near the center of the dome.

  The controller 94 controls on / off of the fan 66 and the heater 68 according to the temperature detected by the temperature sensor 62 and the humidity detected by the humidity sensor 92.

  FIG. 9 shows a map used by the control unit 94 to control the fan 66 and the heater 68. Preferably, the control unit 94 is a microcomputer, stores the map of FIG. 9, and controls the fan 66 and the heater 68 with reference to the map.

  In FIG. 9, when the combination of temperature and humidity is in the region below the line L in FIG. 9 (the shaded region), the control unit 94 operates according to the already described FIG. 6. That is, the control unit 94 controls the fan 66 and the heater 68 according to the temperature detected by the temperature sensor 62. This control is as already described.

  On the other hand, the control unit 94 always turns on the fan 66 and the heater 68 when the combination of temperature and humidity is in the region of the line L or higher.

  As described above, the control of this embodiment performs the control of FIG. 9 in addition to the control of FIG. 6 described above. In the control of FIG. 6, as already described, the fan 66 and the heater 68 are operated when the temperature is lowered, and condensation can be effectively prevented. Furthermore, according to the control in FIG. 9, the fan 66 and the heater 68 are operated to prevent condensation even when the humidity is high, even in a high temperature region, according to the line L that descends to the right.

  According to the third embodiment of the present invention described above, by controlling the fan 66 and the heater 68 according to the temperature and humidity, the operation of the fan 66 and the heater 68 according to the likelihood of condensation. The fan 66 and the heater 68 can be operated as necessary, and power consumption can be suppressed. When the atmosphere near the dome is in a state where condensation is likely to occur while suppressing power consumption, the fan 66 and the heater 68 can be operated to effectively suppress condensation.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and it goes without saying that those skilled in the art can modify the above-described embodiments within the scope of the present invention.

  As described above, the camera device according to the present invention has an effect that the condensation of the window member can be efficiently prevented, and is useful as an outdoor monitoring camera or the like.

Sectional drawing of the camera apparatus in the 1st Embodiment of this invention The perspective view of the camera apparatus in the 1st Embodiment of this invention 1 is an exploded view of a camera device according to a first embodiment of the present invention. 1 is an exploded view of a camera device according to a first embodiment of the present invention. The block diagram of the structure for control of the dew condensation prevention apparatus in the 1st Embodiment of this invention The figure which shows control of the dew condensation prevention apparatus in the 1st Embodiment of this invention The figure which shows the dew condensation prevention apparatus of the camera apparatus in the 2nd Embodiment of this invention. The block diagram of the structure for control of the dew condensation prevention apparatus in the 3rd Embodiment of this invention The figure which shows control of the dew condensation prevention apparatus in the 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Camera apparatus 12 Base 14 Cover 16 Lens 18 Lens barrel 22 Dome 40 Condensation prevention apparatus 42 Fan heater unit 44 Nozzle 46 Slip collar 48 Discharge port 50 Holding ring 60 Control apparatus 62 Temperature sensor 64 Control part 66 Fan 68 Heater

Claims (6)

A window member for shooting;
A lens disposed inside the window member and capable of changing a direction;
A fan that generates wind to prevent condensation;
A nozzle that is held on the side of the lens so as to change the direction together with the lens, and discharges the wind generated by the fan;
A camera device comprising:   The camera apparatus according to claim 1, further comprising a heater for supplying warm air to the nozzle.   The camera device according to claim 1, further comprising a slip collar rotatably attached to the lens barrel, wherein the nozzle is attached to the slip collar.   The camera device according to claim 1, wherein a plurality of nozzles are provided around the lens.   The temperature sensor and the humidity sensor, and fan heater control means for controlling the fan and the heater according to the temperature and humidity detected by the temperature sensor and the humidity sensor are provided. Camera device. A fan that generates wind to prevent condensation;
A nozzle for discharging the wind generated by the fan;
Nozzle holding means for holding the nozzle beside a lens capable of changing the direction of being arranged inside the window member for photographing;
Condensation prevention device characterized by comprising:

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